[PATCH v9 0/2] Add AMD I3C master controller driver and bindings

[PATCH v9 0/2] Add AMD I3C master controller driver and bindings

[Shubham Patil]

This patch series introduces support for the AMD I3C master controller,
including the device tree binding and driver implementation.

Compared to v8, the big-endian MMIO accessor and i3c FIFO-endianness
patches have been dropped; the driver now handles big-endian FIFO
accesses internally.

Note: There was an extended gap since v8 due to the transfer of ownership
of this series from Manikanta to Shubham. This transition contributed
to the delay in releasing the v9 update addressing the v8 review comments.
We appreciate your patience.
---
Changes for V9:
Dropped the three big-endian MMIO/FIFO infrastructure patches; the
driver now handles big-endian FIFO accesses internally.
Replaced the async transfer-queue with a synchronous transfer path.
Reworked error/response handling using enum i3c_error_code and proper
-ENODEV/-EIO returns; propagate err to CCCs and priv xfers.
Switched to the new .i3c_xfers op (reject non-SDR, report actual_len).
Reworked DAA (incremental address assignment, -ENOSPC bound, -ENODEV
end-of-enumeration, checked device registration).
Avoid busy-spin with usleep_range(); use FIELD_PREP() and inline
helpers; split the timeout macros with documented units.
Dropped ENTHDR (SDR-only); updated MAINTAINERS, Kconfig symbol
(AMD_AXI_I3C_MASTER), authors and binding maintainers.

Changes for V8:
Included dependent patch "i3c: fix big-endian FIFO transfers"
to this series as [3/5].
Resolved conflicts with "i3c: fix big-endian FIFO transfers".
Updated description.
Used time_left instead of timeout.
Used __free(kfree) for xfer to simplify err path in multiple places.

Changes for V7:
Added i3c controller version details to commit description.
Added Reviewed-by tag to binding patch [1/4].
Added big-endian MMIO accessors [2/4].
Added endianness support for i3c_readl_fifo() and i3c_writel_fifo() [3/4].
Updated timeout macro name.
Updated xi3c_master_wr_to_tx_fifo() and xi3c_master_rd_from_rx_fifo()
to use i3c_writel_fifo() and i3c_readl_fifo().

Changes for V6:
Corrected the $id in the YAML file to match the filename and fix
the dtschema warning.
Removed typecast for xi3c_getrevisionnumber(), xi3c_wrfifolevel(),
and xi3c_rdfifolevel().
Replaced dynamic allocation with a static variable for pid_bcr_dcr.
Fixed sparse warning in do_daa by typecasting the address parity value
to u8.
Fixed sparse warning in xi3c_master_bus_init by typecasting the pid value
to u64 in info.pid calculation.

Changes for V5:
Renamed the xlnx,axi-i3c.yaml file into xlnx,axi-i3c-1.0.yaml.
Used GENMASK_ULL for PID mask as it's 64bit mask.

Changes for V4:
Added h/w documentation details.
Updated timeout macros.
Removed type casting for xi3c_is_resp_available() macro.
Used ioread32() and iowrite32() instead of readl() and writel()
to keep consistency.
Read XI3C_RESET_OFFSET reg before udelay().
Removed xi3c_master_free_xfer() and directly used kfree().
Skipped checking return value of i3c_master_add_i3c_dev_locked().
Used devm_mutex_init() instead of mutex_init().

Changes for V3:
Updated commit description.
Corrected the order of properties and removed resets property.
Added compatible to required list.
Added interrupts to example.
Resolved merge conflicts.

Changes for V2:
Updated commit subject and description.
Moved allOf to after required.
Removed xlnx,num-targets property.
Added mixed mode support with clock configuration.
Converted smaller functions into inline functions.
Used FIELD_GET() in xi3c_get_response().
Updated xi3c_master_rd_from_rx_fifo() to use cmd->rx_buf.
Used parity8() for address parity calculation.
Added guards for locks.
Dropped num_targets and updated xi3c_master_do_daa().
Used __free(kfree) in xi3c_master_send_bdcast_ccc_cmd().
Dropped PM runtime support.
Updated xi3c_master_read() and xi3c_master_write() with
xi3c_is_resp_available() check.
Created separate functions: xi3c_master_init() and xi3c_master_reinit().
Used xi3c_master_init() in bus initialization and xi3c_master_reinit()
in error paths.
Added DAA structure to xi3c_master structure.
---
Manikanta Guntupalli (2):
  dt-bindings: i3c: Add AMD I3C master controller support
  i3c: master: Add driver for AMD AXI I3C master controller

 .../bindings/i3c/xlnx,axi-i3c-1.0.yaml        |   56 +
 MAINTAINERS                                   |    8 +
 drivers/i3c/master/Kconfig                    |   15 +
 drivers/i3c/master/Makefile                   |    1 +
 drivers/i3c/master/amd-i3c-master.c           | 1060 +++++++++++++++++
 5 files changed, 1140 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/i3c/xlnx,axi-i3c-1.0.yaml
 create mode 100644 drivers/i3c/master/amd-i3c-master.c

-- 
2.34.1

[PATCH v9 1/2] dt-bindings: i3c: Add AMD I3C master controller support

[Shubham Patil]

From: Manikanta Guntupalli <manikanta.guntupalli@amd.com>

Add device tree binding documentation for the AMD I3C master controller
version 1.0.

Signed-off-by: Manikanta Guntupalli <manikanta.guntupalli@amd.com>
Reviewed-by: Rob Herring (Arm) <robh@kernel.org>
---
Changes for V9:
None.

Changes for V8:
None.

Changes for V7:
Added i3c controller version details to commit description.

Changes for V6:
Corrected the file name for $id in yaml to fix the dtschema warning.

Changes for V5:
Renamed the xlnx,axi-i3c.yaml file into xlnx,axi-i3c-1.0.yaml.

Changes for V4:
Added h/w documentation details.

Changes for V3:
Updated commit description.
Corrected the order of properties and removed resets property.
Added compatible to required list.
Added interrupts to example.

Changes for V2:
Updated commit subject and description.
Moved allOf to after required.
Removed xlnx,num-targets property.
---
 .../bindings/i3c/xlnx,axi-i3c-1.0.yaml        | 56 +++++++++++++++++++
 1 file changed, 56 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/i3c/xlnx,axi-i3c-1.0.yaml

diff --git a/Documentation/devicetree/bindings/i3c/xlnx,axi-i3c-1.0.yaml b/Documentation/devicetree/bindings/i3c/xlnx,axi-i3c-1.0.yaml
new file mode 100644
index 000000000000..75f677696f02
--- /dev/null
+++ b/Documentation/devicetree/bindings/i3c/xlnx,axi-i3c-1.0.yaml
@@ -0,0 +1,56 @@
+# SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/i3c/xlnx,axi-i3c-1.0.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: AMD I3C master
+
+maintainers:
+  - Shubhrajyoti Datta <shubhrajyoti.datta@amd.com>
+  - Shubham Patil <shubhamsanjay.patil@amd.com>
+
+description:
+  The AXI-I3C IP is an I3C Controller with an AXI4-Lite interface, compatible
+  with the MIPI I3C Specification v1.1.1. The design includes bidirectional I/O
+  buffers that implement open collector drivers for the SDA and SCL signals.
+  External pull-up resistors are required to properly hold the bus at a Logic-1
+  level when the drivers are released.
+
+  For more details, please see https://docs.amd.com/r/en-US/pg439-axi-i3c
+
+properties:
+  compatible:
+    const: xlnx,axi-i3c-1.0
+
+  reg:
+    maxItems: 1
+
+  clocks:
+    maxItems: 1
+
+  interrupts:
+    maxItems: 1
+
+required:
+  - compatible
+  - reg
+  - clocks
+
+allOf:
+  - $ref: i3c.yaml#
+
+unevaluatedProperties: false
+
+examples:
+  - |
+    i3c@80000000 {
+        compatible = "xlnx,axi-i3c-1.0";
+        reg = <0x80000000 0x10000>;
+        clocks = <&zynqmp_clk 71>;
+        interrupt-parent = <&imux>;
+        interrupts = <0 89 4>;
+        #address-cells = <3>;
+        #size-cells = <0>;
+    };
+...
-- 
2.34.1

[PATCH v9 2/2] i3c: master: Add driver for AMD AXI I3C master controller

[Shubham Patil]

From: Manikanta Guntupalli <manikanta.guntupalli@amd.com>

Add an I3C master driver and maintainers fragment for the AMD I3C bus
controller.

The driver currently supports the I3C bus operating in SDR mode,
with features including Dynamic Address Assignment, private data
transfers, and CCC transfers in both broadcast and direct modes. It
also supports operation in I2C mode.

The controller's data FIFOs are accessed big-endian; the driver performs
this conversion locally using ioread32be()/iowrite32be() with the
helpers, so it does not depend on any core FIFO-endianness helpers.

Signed-off-by: Manikanta Guntupalli <manikanta.guntupalli@amd.com>
Co-developed-by: Shubhrajyoti Datta <shubhrajyoti.datta@amd.com>
Signed-off-by: Shubhrajyoti Datta <shubhrajyoti.datta@amd.com>
Co-developed-by: Shubham Patil <shubhamsanjay.patil@amd.com>
Signed-off-by: Shubham Patil <shubhamsanjay.patil@amd.com>
---
Changes for V9:
Updated commit description to note that the driver performs big-endian
FIFO accesses locally (the v8 core-helper patches were dropped).
Dropped the big-endian MMIO infrastructure patches from the series
("asm-generic/io.h: Add big-endian MMIO accessors", "i3c: fix
big-endian FIFO transfers", and "i3c: master: Add endianness support
for i3c_readl_fifo()/i3c_writel_fifo()"). The driver now performs
big-endian FIFO accesses locally using ioread32be()/iowrite32be() with
get_unaligned()/put_unaligned(), so the series is self-contained and no
longer includes internals.h.
Replaced the async completion/transfer-queue machinery with a simple
synchronous transfer path under the existing mutex.
Reworked response handling: added enum i3c_error_code to struct
xi3c_cmd, named the response codes, return -ENODEV/-EIO as appropriate
and set err = I3C_ERROR_M2/M0 so the i3c core and callers can tell a
NACK apart from a bus error; propagate err to CCC commands and to each
priv xfer (including actual_len).
Switched from .priv_xfers to the new .i3c_xfers op; reject non-SDR
modes with -EOPNOTSUPP and report actual_len.
Reworked DAA: assign addresses incrementally, bound the device count
(-ENOSPC), detect end-of-enumeration via -ENODEV, zero-initialize the
PID buffers, and check i3c_master_add_i3c_dev_locked().
Avoid busy-spinning: sleep with usleep_range() in the FIFO drain/fill
loops.
Use FIELD_PREP() with named command-FIFO field masks instead of
open-coded shifts, and convert the register-accessor macros to inline
functions.
Split the overloaded timeout macro into XI3C_RESP_TIMEOUT_US and
XI3C_XFER_TIMEOUT_MS with documented units, and add
XI3C_POLL_INTERVAL_US.
xi3c_clk_cfg(): use NSEC_PER_SEC and named timing constants, guard
against unsigned underflow, and handle I3C_BUS_MODE_MIXED_SLOW.
Dropped ENTHDR from supports_ccc_cmd() (SDR-only), and dispatch CCCs
using the I3C_CCC_DIRECT bit.
Use const for TX buffers and drop the related casts; use parity8() for
the DAA parity bit.
Updated MODULE_DESCRIPTION and authors, the copyright year, renamed the
Kconfig symbol to AMD_AXI_I3C_MASTER, and fixed the MAINTAINERS entry
(title, mailing list, and the correct binding filename).

Changes for V8:
Used time_left instead of timeout.
Used __free(kfree) for xfer to simplify err path in multiple places.

Changes for V7:
Updated timeout macro name.
Updated xi3c_master_wr_to_tx_fifo() and xi3c_master_rd_from_rx_fifo()
to use i3c_writel_fifo() and i3c_readl_fifo().

Changes for V6:
Removed typecast for xi3c_getrevisionnumber(), xi3c_wrfifolevel(),
and xi3c_rdfifolevel().
Replaced dynamic allocation with a static variable for pid_bcr_dcr.
Fixed sparse warning in do_daa by typecasting the address parity value
to u8.
Fixed sparse warning in xi3c_master_bus_init by typecasting the pid value
to u64 in info.pid calculation.

Changes for V5:
Used GENMASK_ULL for PID mask as it's 64bit mask.

Changes for V4:
Updated timeout macros.
Removed type casting for xi3c_is_resp_available() macro.
Used ioread32() and iowrite32() instead of readl() and writel()
to keep consistency.
Read XI3C_RESET_OFFSET reg before udelay().
Removed xi3c_master_free_xfer() and directly used kfree().
Skipped checking return value of i3c_master_add_i3c_dev_locked().
Used devm_mutex_init() instead of mutex_init().

Changes for V3:
Resolved merge conflicts.

Changes for V2:
Updated commit description.
Added mixed mode support with clock configuration.
Converted smaller functions into inline functions.
Used FIELD_GET() in xi3c_get_response().
Updated xi3c_master_rd_from_rx_fifo() to use cmd->rx_buf.
Used parity8() for address parity calculation.
Added guards for locks.
Dropped num_targets and updated xi3c_master_do_daa().
Used __free(kfree) in xi3c_master_send_bdcast_ccc_cmd().
Dropped PM runtime support.
Updated xi3c_master_read() and xi3c_master_write() with
xi3c_is_resp_available() check.
Created separate functions: xi3c_master_init() and xi3c_master_reinit().
Used xi3c_master_init() in bus initialization and xi3c_master_reinit()
in error paths.
Added DAA structure to xi3c_master structure.
---
 MAINTAINERS                         |    8 +
 drivers/i3c/master/Kconfig          |   15 +
 drivers/i3c/master/Makefile         |    1 +
 drivers/i3c/master/amd-i3c-master.c | 1060 +++++++++++++++++++++++++++
 4 files changed, 1084 insertions(+)
 create mode 100644 drivers/i3c/master/amd-i3c-master.c

diff --git a/MAINTAINERS b/MAINTAINERS
index 461a3eed6129..bfaa6999913c 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -1035,6 +1035,14 @@ L:	linux-sound@vger.kernel.org
 S:	Supported
 F:	sound/soc/amd/
 
+AMD AXI I3C MASTER DRIVER
+M:	Shubhrajyoti Datta <shubhrajyoti.datta@amd.com>
+M:	Shubham Patil <shubhamsanjay.patil@amd.com>
+L:	linux-i3c@lists.infradead.org
+S:	Maintained
+F:	Documentation/devicetree/bindings/i3c/xlnx,axi-i3c-1.0.yaml
+F:	drivers/i3c/master/amd-i3c-master.c
+
 AMD AXI W1 DRIVER
 M:	Kris Chaplin <kris.chaplin@amd.com>
 R:	Thomas Delev <thomas.delev@amd.com>
diff --git a/drivers/i3c/master/Kconfig b/drivers/i3c/master/Kconfig
index 2609f2b18e0a..da96d2aaa399 100644
--- a/drivers/i3c/master/Kconfig
+++ b/drivers/i3c/master/Kconfig
@@ -86,3 +86,18 @@ config RENESAS_I3C
 
 	  This driver can also be built as a module. If so, the module will be
 	  called renesas-i3c.
+
+config AMD_AXI_I3C_MASTER
+	tristate "AMD AXI I3C Master driver"
+	depends on HAS_IOMEM
+	help
+	  Support for the AMD AXI I3C master controller, a soft IP used on
+	  AMD (Xilinx) FPGAs and adaptive SoCs with ARM or MicroBlaze
+	  processors.
+
+	  The controller currently supports Standard Data Rate (SDR) mode.
+	  Features include Dynamic Address Assignment, private transfers,
+	  and CCC transfers in both broadcast and direct modes.
+
+	  This driver can also be built as a module. If so, the module
+	  will be called amd-i3c-master.
diff --git a/drivers/i3c/master/Makefile b/drivers/i3c/master/Makefile
index 816a227b6f7a..8d82196dcf83 100644
--- a/drivers/i3c/master/Makefile
+++ b/drivers/i3c/master/Makefile
@@ -6,3 +6,4 @@ obj-$(CONFIG_AST2600_I3C_MASTER)	+= ast2600-i3c-master.o
 obj-$(CONFIG_SVC_I3C_MASTER)		+= svc-i3c-master.o
 obj-$(CONFIG_MIPI_I3C_HCI)		+= mipi-i3c-hci/
 obj-$(CONFIG_RENESAS_I3C)		+= renesas-i3c.o
+obj-$(CONFIG_AMD_AXI_I3C_MASTER)	+= amd-i3c-master.o
diff --git a/drivers/i3c/master/amd-i3c-master.c b/drivers/i3c/master/amd-i3c-master.c
new file mode 100644
index 000000000000..34ab1028c3ce
--- /dev/null
+++ b/drivers/i3c/master/amd-i3c-master.c
@@ -0,0 +1,1060 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * I3C master driver for the AMD I3C controller.
+ *
+ * Copyright (C) 2026, Advanced Micro Devices, Inc.
+ */
+
+#include <linux/bitfield.h>
+#include <linux/bitops.h>
+#include <linux/cleanup.h>
+#include <linux/clk.h>
+#include <linux/delay.h>
+#include <linux/err.h>
+#include <linux/i3c/master.h>
+#include <linux/io.h>
+#include <linux/iopoll.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/time.h>
+#include <linux/unaligned.h>
+
+#define XI3C_VERSION_OFFSET			0x00	/* Version Register */
+#define XI3C_RESET_OFFSET			0x04	/* Soft Reset Register */
+#define XI3C_CR_OFFSET				0x08	/* Control Register */
+#define XI3C_ADDRESS_OFFSET			0x0C	/* Target Address Register */
+#define XI3C_SR_OFFSET				0x10	/* Status Register */
+#define XI3C_CMD_FIFO_OFFSET			0x20	/* I3C Command FIFO Register */
+#define XI3C_WR_FIFO_OFFSET			0x24	/* I3C Write Data FIFO Register */
+#define XI3C_RD_FIFO_OFFSET			0x28	/* I3C Read Data FIFO Register */
+#define XI3C_RESP_STATUS_FIFO_OFFSET		0x2C	/* I3C Response status FIFO Register */
+#define XI3C_FIFO_LVL_STATUS_OFFSET		0x30	/* CMD slots free | WR-FIFO free (words) */
+#define XI3C_FIFO_LVL_STATUS_1_OFFSET		0x34	/* RESP fill | RD-FIFO fill level (words) */
+#define XI3C_SCL_HIGH_TIME_OFFSET		0x38	/* I3C SCL HIGH Register */
+#define XI3C_SCL_LOW_TIME_OFFSET		0x3C	/* I3C SCL LOW Register */
+#define XI3C_SDA_HOLD_TIME_OFFSET		0x40	/* I3C SDA HOLD Register */
+#define XI3C_TSU_START_OFFSET			0x48	/* I3C START SETUP Register */
+#define XI3C_THD_START_OFFSET			0x4C	/* I3C START HOLD Register */
+#define XI3C_TSU_STOP_OFFSET			0x50	/* I3C STOP Setup Register */
+#define XI3C_OD_SCL_HIGH_TIME_OFFSET		0x54	/* I3C OD SCL HIGH Register */
+#define XI3C_OD_SCL_LOW_TIME_OFFSET		0x58	/* I3C OD SCL LOW Register */
+#define XI3C_PID0_OFFSET			0x6C	/* LSB 4 bytes of the PID */
+#define XI3C_PID1_BCR_DCR			0x70	/* MSB 2 bytes of the PID, BCR and DCR */
+
+#define XI3C_CR_EN_MASK				BIT(0)	/* Core Enable */
+#define XI3C_CR_RESUME_MASK			BIT(2)	/* Core Resume */
+#define XI3C_SR_RESP_NOT_EMPTY_MASK		BIT(4)	/* Resp Fifo not empty status mask */
+#define XI3C_RD_FIFO_NOT_EMPTY_MASK		BIT(15)	/* Read Fifo not empty status mask */
+
+#define XI3C_BCR_MASK				GENMASK(23, 16)
+#define XI3C_DCR_MASK				GENMASK(31, 24)
+#define XI3C_PID_MASK				GENMASK_ULL(63, 16)
+#define XI3C_TIMING_MASK			GENMASK(17, 0)
+#define XI3C_REV_NUM_MASK			GENMASK(15, 8)
+#define XI3C_PID1_MASK				GENMASK(15, 0)
+#define XI3C_FIFO_LEVEL_MASK			GENMASK(15, 0)
+#define XI3C_RESP_CODE_MASK			GENMASK(8, 5)
+#define XI3C_RESP_CODE_SUCCESS			0	/* Transfer completed OK */
+#define XI3C_RESP_CODE_NO_TARGET		2	/* 7E NACK: no target on bus */
+#define XI3C_RESP_CODE_NACK			3	/* Target NACK / CE2 / DAA end */
+#define XI3C_ADDR_MASK				GENMASK(6, 0)
+#define XI3C_FIFOS_RST_MASK			GENMASK(4, 1)
+
+/* Command FIFO word layout (bit ranges encoded in the GENMASK/BIT args) */
+#define XI3C_CMD_TYPE				GENMASK(3, 0)	/* command type */
+#define XI3C_CMD_TERMINATE			BIT(4)		/* terminate (last cmd of xfer) */
+#define XI3C_CMD_ADDR				GENMASK(15, 8)	/* target address << 1 | RnW */
+#define XI3C_CMD_LEN				GENMASK(27, 16)	/* payload length in bytes */
+#define XI3C_CMD_TID				GENMASK(31, 28)	/* transfer ID */
+
+#define XI3C_OD_TLOW_NS				500000
+#define XI3C_OD_THIGH_NS			41000
+#define XI3C_I2C_TCASMIN_NS			600000
+#define XI3C_TCASMIN_NS				260000
+#define XI3C_MAXDATA_LENGTH			4095
+#define XI3C_MAX_DEVS				32
+#define XI3C_DAA_SLAVEINFO_READ_BYTECOUNT	8
+
+#define XI3C_THOLD_MIN_REV0			5	/* Min SDA hold cycles, rev 0 IP */
+#define XI3C_THOLD_MIN_REV1			6	/* Min SDA hold cycles, rev >= 1 IP */
+#define XI3C_CYCLE_ADJUST			2	/* SCL/SDA pre-bias for HW pipeline */
+#define XI3C_FIFO_RESET_DELAY_US		10	/* HW settling time after FIFO reset */
+#define XI3C_POLL_INTERVAL_US			10	/* readl_poll_timeout() sleep slice */
+
+#define XI3C_I2C_MODE				0
+#define XI3C_I2C_TID				0
+#define XI3C_SDR_MODE				1
+#define XI3C_SDR_TID				1
+
+#define XI3C_WORD_LEN				4
+
+/*
+ * XI3C_RESP_TIMEOUT_US is in microseconds because it is passed as the
+ * timeout_us argument of readl_poll_timeout(). XI3C_XFER_TIMEOUT_MS is in
+ * milliseconds because it feeds msecs_to_jiffies(). Keep the two units
+ * distinct in the names so callers cannot mix them up.
+ */
+#define XI3C_RESP_TIMEOUT_US			500000
+#define XI3C_XFER_TIMEOUT_MS			1000
+
+struct xi3c_cmd {
+	const void *tx_buf;
+	void *rx_buf;
+	u16 tx_len;
+	u16 rx_len;
+	u8 addr;
+	u8 type;
+	u8 tid;
+	bool rnw;
+	bool is_daa;
+	bool continued;
+	enum i3c_error_code err;
+};
+
+struct xi3c_xfer {
+	unsigned int ncmds;
+	struct xi3c_cmd cmds[] __counted_by(ncmds);
+};
+
+/**
+ * struct xi3c_master - I3C master controller state.
+ * @base: I3C master controller embedded by the framework.
+ * @dev: Pointer to the backing device structure.
+ * @membase: Memory base of the HW registers.
+ * @pclk: Input clock driving the controller.
+ * @lock: Serializes transfers and CCC submission.
+ * @daa: ENTDAA enumeration state.
+ * @daa.addrs: Dynamic addresses assigned in enumeration order.
+ * @daa.index: Number of responders enumerated so far.
+ */
+struct xi3c_master {
+	struct i3c_master_controller base;
+	struct device *dev;
+	void __iomem *membase;
+	struct clk *pclk;
+	struct mutex lock; /* serializes transfers and CCC submission */
+	struct {
+		u8 addrs[XI3C_MAX_DEVS];
+		u8 index;
+	} daa;
+};
+
+static inline struct xi3c_master *
+to_xi3c_master(struct i3c_master_controller *master)
+{
+	return container_of(master, struct xi3c_master, base);
+}
+
+static inline u8 xi3c_get_revision_number(struct xi3c_master *master)
+{
+	return FIELD_GET(XI3C_REV_NUM_MASK,
+			 ioread32(master->membase + XI3C_VERSION_OFFSET));
+}
+
+static inline u16 xi3c_wr_fifo_level(struct xi3c_master *master)
+{
+	return ioread32(master->membase + XI3C_FIFO_LVL_STATUS_OFFSET) &
+	       XI3C_FIFO_LEVEL_MASK;
+}
+
+static inline u16 xi3c_rd_fifo_level(struct xi3c_master *master)
+{
+	return ioread32(master->membase + XI3C_FIFO_LVL_STATUS_1_OFFSET) &
+	       XI3C_FIFO_LEVEL_MASK;
+}
+
+static inline bool xi3c_is_resp_available(struct xi3c_master *master)
+{
+	return FIELD_GET(XI3C_SR_RESP_NOT_EMPTY_MASK,
+			 ioread32(master->membase + XI3C_SR_OFFSET));
+}
+
+static int xi3c_get_response(struct xi3c_master *master, struct xi3c_cmd *cmd)
+{
+	u32 response_data;
+	u32 resp_reg;
+	u8 code;
+	int ret;
+
+	ret = readl_poll_timeout(master->membase + XI3C_SR_OFFSET,
+				 resp_reg,
+				 resp_reg & XI3C_SR_RESP_NOT_EMPTY_MASK,
+				 XI3C_POLL_INTERVAL_US, XI3C_RESP_TIMEOUT_US);
+	if (ret) {
+		dev_err(master->dev, "XI3C response timeout\n");
+		return ret;
+	}
+
+	response_data = ioread32(master->membase + XI3C_RESP_STATUS_FIFO_OFFSET);
+	code = FIELD_GET(XI3C_RESP_CODE_MASK, response_data);
+
+	switch (code) {
+	case XI3C_RESP_CODE_SUCCESS:
+		cmd->err = I3C_ERROR_UNKNOWN;
+		return 0;
+	case XI3C_RESP_CODE_NO_TARGET:
+	case XI3C_RESP_CODE_NACK:
+		/*
+		 * Target did not ACK. Record it as I3C_ERROR_M2 so callers
+		 * (and the i3c core, which keys on err == I3C_ERROR_M2) can
+		 * tell a NACK apart from other failures. A normal transfer
+		 * surfaces this as -EIO per the i3c_xfer contract; the DAA
+		 * path instead expects -ENODEV as its enumeration terminator.
+		 */
+		cmd->err = I3C_ERROR_M2;
+		return cmd->is_daa ? -ENODEV : -EIO;
+	default:
+		cmd->err = I3C_ERROR_M0;
+		dev_err(master->dev, "XI3C transfer error, response code %u\n",
+			code);
+		return -EIO;
+	}
+}
+
+static inline void xi3c_writesl_be(void __iomem *addr, const void *buffer,
+				   unsigned int count)
+{
+	const u32 *buf = buffer;
+
+	while (count--)
+		iowrite32be(get_unaligned(buf++), addr);
+}
+
+static inline void xi3c_readsl_be(const void __iomem *addr, void *buffer,
+				  unsigned int count)
+{
+	u32 *buf = buffer;
+
+	while (count--)
+		put_unaligned(ioread32be(addr), buf++);
+}
+
+static inline void xi3c_writel_fifo(void __iomem *addr, const void *buf,
+				    int nbytes)
+{
+	xi3c_writesl_be(addr, buf, nbytes / 4);
+	if (nbytes & 3) {
+		u32 tmp = 0;
+
+		memcpy(&tmp, (const u8 *)buf + (nbytes & ~3), nbytes & 3);
+		xi3c_writesl_be(addr, &tmp, 1);
+	}
+}
+
+static inline void xi3c_readl_fifo(const void __iomem *addr, void *buf,
+				   int nbytes)
+{
+	xi3c_readsl_be(addr, buf, nbytes / 4);
+	if (nbytes & 3) {
+		u32 tmp;
+
+		xi3c_readsl_be(addr, &tmp, 1);
+		memcpy((u8 *)buf + (nbytes & ~3), &tmp, nbytes & 3);
+	}
+}
+
+static void xi3c_master_write_to_cmdfifo(struct xi3c_master *master,
+					 struct xi3c_cmd *cmd, u16 len)
+{
+	u32 transfer_cmd;
+	u8 addr;
+
+	addr = ((cmd->addr & XI3C_ADDR_MASK) << 1) | (u8)cmd->rnw;
+
+	transfer_cmd  = FIELD_PREP(XI3C_CMD_TYPE, cmd->type);
+	transfer_cmd |= FIELD_PREP(XI3C_CMD_TERMINATE, !cmd->continued);
+	transfer_cmd |= FIELD_PREP(XI3C_CMD_ADDR, addr);
+	transfer_cmd |= FIELD_PREP(XI3C_CMD_TID, cmd->tid);
+
+	/*
+	 * For dynamic addressing, an additional 1-byte length must be added
+	 * to the command FIFO to account for the address present in the TX FIFO
+	 */
+	if (cmd->is_daa) {
+		xi3c_writel_fifo(master->membase + XI3C_WR_FIFO_OFFSET,
+				 cmd->tx_buf, cmd->tx_len);
+
+		len++;
+	}
+
+	transfer_cmd |= FIELD_PREP(XI3C_CMD_LEN, len);
+	iowrite32(transfer_cmd, master->membase + XI3C_CMD_FIFO_OFFSET);
+}
+
+static inline void xi3c_master_enable(struct xi3c_master *master)
+{
+	iowrite32(ioread32(master->membase + XI3C_CR_OFFSET) | XI3C_CR_EN_MASK,
+		  master->membase + XI3C_CR_OFFSET);
+}
+
+static inline void xi3c_master_disable(struct xi3c_master *master)
+{
+	iowrite32(ioread32(master->membase + XI3C_CR_OFFSET) & ~XI3C_CR_EN_MASK,
+		  master->membase + XI3C_CR_OFFSET);
+}
+
+static inline void xi3c_master_resume(struct xi3c_master *master)
+{
+	iowrite32(ioread32(master->membase + XI3C_CR_OFFSET) |
+		  XI3C_CR_RESUME_MASK, master->membase + XI3C_CR_OFFSET);
+}
+
+static void xi3c_master_reset_fifos(struct xi3c_master *master)
+{
+	u32 data;
+
+	/* Assert FIFO reset. */
+	data = ioread32(master->membase + XI3C_RESET_OFFSET);
+	data |= XI3C_FIFOS_RST_MASK;
+	iowrite32(data, master->membase + XI3C_RESET_OFFSET);
+	/* Read-back flushes the posted write before the settling delay below. */
+	ioread32(master->membase + XI3C_RESET_OFFSET);
+	udelay(XI3C_FIFO_RESET_DELAY_US);
+
+	/* De-assert FIFO reset, then wait for the FIFOs to come back up. */
+	data &= ~XI3C_FIFOS_RST_MASK;
+	iowrite32(data, master->membase + XI3C_RESET_OFFSET);
+	ioread32(master->membase + XI3C_RESET_OFFSET);
+	udelay(XI3C_FIFO_RESET_DELAY_US);
+}
+
+static inline void xi3c_master_init(struct xi3c_master *master)
+{
+	/* Reset fifos */
+	xi3c_master_reset_fifos(master);
+
+	/* Enable controller */
+	xi3c_master_enable(master);
+}
+
+static inline void xi3c_master_reinit(struct xi3c_master *master)
+{
+	/* Reset fifos */
+	xi3c_master_reset_fifos(master);
+
+	/* Resume controller */
+	xi3c_master_resume(master);
+}
+
+static struct xi3c_xfer *xi3c_master_alloc_xfer(unsigned int ncmds)
+{
+	struct xi3c_xfer *xfer;
+
+	xfer = kzalloc(struct_size(xfer, cmds, ncmds), GFP_KERNEL);
+	if (!xfer)
+		return NULL;
+
+	xfer->ncmds = ncmds;
+
+	return xfer;
+}
+
+static void xi3c_master_rd_from_rx_fifo(struct xi3c_master *master,
+					struct xi3c_cmd *cmd)
+{
+	u16 rx_data_available;
+	u16 copy_len;
+	u16 len;
+
+	rx_data_available = xi3c_rd_fifo_level(master);
+	len = rx_data_available * XI3C_WORD_LEN;
+
+	if (!len)
+		return;
+
+	copy_len = min_t(u16, len, cmd->rx_len);
+	xi3c_readl_fifo(master->membase + XI3C_RD_FIFO_OFFSET,
+			(u8 *)cmd->rx_buf, copy_len);
+
+	cmd->rx_buf = (u8 *)cmd->rx_buf + copy_len;
+	cmd->rx_len -= copy_len;
+}
+
+static int xi3c_master_read(struct xi3c_master *master, struct xi3c_cmd *cmd)
+{
+	unsigned long timeout;
+	u32 status_reg;
+	int ret;
+
+	if (!cmd->rx_buf || cmd->rx_len > XI3C_MAXDATA_LENGTH)
+		return -EINVAL;
+
+	/* Fill command fifo */
+	xi3c_master_write_to_cmdfifo(master, cmd, cmd->rx_len);
+
+	if (!cmd->rx_len)
+		return 0;
+
+	ret = readl_poll_timeout(master->membase + XI3C_SR_OFFSET,
+				 status_reg,
+				 status_reg & (XI3C_RD_FIFO_NOT_EMPTY_MASK |
+					       XI3C_SR_RESP_NOT_EMPTY_MASK),
+				 XI3C_POLL_INTERVAL_US, XI3C_RESP_TIMEOUT_US);
+	if (ret) {
+		dev_err(master->dev, "XI3C read timeout\n");
+		return ret;
+	}
+
+	if (!(status_reg & XI3C_RD_FIFO_NOT_EMPTY_MASK))
+		return 0;
+
+	timeout = jiffies + msecs_to_jiffies(XI3C_XFER_TIMEOUT_MS);
+
+	/* Read data from rx fifo */
+	while (cmd->rx_len > 0 && !xi3c_is_resp_available(master)) {
+		if (time_after(jiffies, timeout)) {
+			dev_err(master->dev, "XI3C read timeout\n");
+			return -EIO;
+		}
+		xi3c_master_rd_from_rx_fifo(master, cmd);
+		usleep_range(XI3C_POLL_INTERVAL_US, 2 * XI3C_POLL_INTERVAL_US);
+	}
+
+	/* Read remaining data */
+	xi3c_master_rd_from_rx_fifo(master, cmd);
+
+	return 0;
+}
+
+static void xi3c_master_wr_to_tx_fifo(struct xi3c_master *master,
+				      struct xi3c_cmd *cmd)
+{
+	u16 wrfifo_space;
+	u16 len;
+
+	wrfifo_space = xi3c_wr_fifo_level(master);
+	if (cmd->tx_len > wrfifo_space * XI3C_WORD_LEN)
+		len = wrfifo_space * XI3C_WORD_LEN;
+	else
+		len = cmd->tx_len;
+
+	if (len) {
+		xi3c_writel_fifo(master->membase + XI3C_WR_FIFO_OFFSET, cmd->tx_buf,
+				 len);
+
+		cmd->tx_buf = (const u8 *)cmd->tx_buf + len;
+		cmd->tx_len -= len;
+	}
+}
+
+static int xi3c_master_write(struct xi3c_master *master, struct xi3c_cmd *cmd)
+{
+	unsigned long timeout;
+	u16 cmd_len;
+
+	if (!cmd->tx_buf || cmd->tx_len > XI3C_MAXDATA_LENGTH)
+		return -EINVAL;
+
+	cmd_len = cmd->tx_len;
+
+	/* Fill Tx fifo */
+	xi3c_master_wr_to_tx_fifo(master, cmd);
+
+	/* Write to command fifo */
+	xi3c_master_write_to_cmdfifo(master, cmd, cmd_len);
+
+	timeout = jiffies + msecs_to_jiffies(XI3C_XFER_TIMEOUT_MS);
+	/* Fill if any remaining data to tx fifo */
+	while (cmd->tx_len > 0 && !xi3c_is_resp_available(master)) {
+		if (time_after(jiffies, timeout)) {
+			dev_err(master->dev, "XI3C write timeout\n");
+			return -EIO;
+		}
+
+		xi3c_master_wr_to_tx_fifo(master, cmd);
+		usleep_range(XI3C_POLL_INTERVAL_US, 2 * XI3C_POLL_INTERVAL_US);
+	}
+
+	return 0;
+}
+
+static int xi3c_master_xfer(struct xi3c_master *master, struct xi3c_cmd *cmd)
+{
+	int ret;
+
+	if (cmd->rnw)
+		ret = xi3c_master_read(master, cmd);
+	else
+		ret = xi3c_master_write(master, cmd);
+
+	if (ret)
+		goto err_xfer_out;
+
+	ret = xi3c_get_response(master, cmd);
+	if (ret)
+		goto err_xfer_out;
+
+	return 0;
+
+err_xfer_out:
+	xi3c_master_reinit(master);
+	return ret;
+}
+
+static int xi3c_master_common_xfer(struct xi3c_master *master,
+				   struct xi3c_xfer *xfer)
+{
+	unsigned int i;
+	int ret;
+
+	guard(mutex)(&master->lock);
+
+	for (i = 0; i < xfer->ncmds; i++) {
+		ret = xi3c_master_xfer(master, &xfer->cmds[i]);
+		if (ret)
+			return ret;
+	}
+
+	return 0;
+}
+
+static int xi3c_master_do_daa(struct i3c_master_controller *m)
+{
+	u8 pid_bufs[XI3C_MAX_DEVS][XI3C_DAA_SLAVEINFO_READ_BYTECOUNT] = {};
+	struct xi3c_master *master = to_xi3c_master(m);
+	struct xi3c_xfer *xfer __free(kfree) = NULL;
+	struct xi3c_cmd *daa_cmd;
+	int addr, ret, i;
+	u8 last_addr = 0;
+	u8 *pid_buf;
+	u8 ccc_id;
+
+	xfer = xi3c_master_alloc_xfer(1);
+	if (!xfer)
+		return -ENOMEM;
+
+	/* Fill ENTDAA CCC */
+	ccc_id = I3C_CCC_ENTDAA;
+	daa_cmd = &xfer->cmds[0];
+	daa_cmd->addr = I3C_BROADCAST_ADDR;
+	daa_cmd->rnw = false;
+	daa_cmd->tx_buf = &ccc_id;
+	daa_cmd->tx_len = 1;
+	daa_cmd->type = XI3C_SDR_MODE;
+	daa_cmd->tid = XI3C_SDR_TID;
+	daa_cmd->continued = true;
+
+	ret = xi3c_master_common_xfer(master, xfer);
+	/*
+	 * A NACK on the ENTDAA broadcast (I3C_ERROR_M2) means no slaves are
+	 * present to enter DAA. Treat as a successful no-op after letting
+	 * err_daa reinitialize the controller.
+	 */
+	if (ret && daa_cmd->err == I3C_ERROR_M2) {
+		ret = 0;
+		goto err_daa;
+	}
+	if (ret)
+		goto err_daa;
+
+	master->daa.index = 0;
+
+	while (true) {
+		struct xi3c_cmd *cmd = &xfer->cmds[0];
+		u8 daa_byte;
+
+		if (master->daa.index >= XI3C_MAX_DEVS) {
+			ret = -ENOSPC;
+			goto err_daa;
+		}
+
+		addr = i3c_master_get_free_addr(m, last_addr + 1);
+		if (addr < 0) {
+			ret = addr;
+			goto err_daa;
+		}
+
+		pid_buf = pid_bufs[master->daa.index];
+
+		daa_byte = (addr << 1) | (parity8(addr) ^ 1);
+
+		cmd->tx_buf = &daa_byte;
+		cmd->tx_len = 1;
+		cmd->addr = I3C_BROADCAST_ADDR;
+		cmd->rnw = true;
+		cmd->rx_buf = pid_buf;
+		cmd->rx_len = XI3C_DAA_SLAVEINFO_READ_BYTECOUNT;
+		cmd->is_daa = true;
+		cmd->type = XI3C_SDR_MODE;
+		cmd->tid = XI3C_SDR_TID;
+		cmd->continued = true;
+
+		ret = xi3c_master_common_xfer(master, xfer);
+
+		/*
+		 * End of enumeration: the next responder NACK'd the
+		 * dynamic-address grant, surfaced as -ENODEV.
+		 * xi3c_master_xfer() has already reset the FIFOs and
+		 * resumed the core for us; just exit the loop and
+		 * register the responders collected so far.
+		 */
+		if (ret == -ENODEV) {
+			ret = 0;
+			break;
+		}
+		if (ret)
+			goto err_daa;
+
+		master->daa.addrs[master->daa.index] = addr;
+		last_addr = addr;
+		master->daa.index++;
+	}
+
+	for (i = 0; i < master->daa.index; i++) {
+		u64 pid;
+
+		ret = i3c_master_add_i3c_dev_locked(m, master->daa.addrs[i]);
+		if (ret)
+			goto err_daa;
+
+		pid = FIELD_GET(XI3C_PID_MASK,
+				get_unaligned_be64(pid_bufs[i]));
+		dev_dbg(master->dev, "Client %d: PID: 0x%llx\n", i, pid);
+	}
+
+	return 0;
+
+err_daa:
+	xi3c_master_reinit(master);
+	return ret;
+}
+
+static bool
+xi3c_master_supports_ccc_cmd(struct i3c_master_controller *master,
+			     const struct i3c_ccc_cmd *cmd)
+{
+	if (cmd->ndests > 1)
+		return false;
+
+	switch (cmd->id) {
+	case I3C_CCC_ENEC(true):
+	case I3C_CCC_ENEC(false):
+	case I3C_CCC_DISEC(true):
+	case I3C_CCC_DISEC(false):
+	case I3C_CCC_ENTAS(0, true):
+	case I3C_CCC_ENTAS(0, false):
+	case I3C_CCC_RSTDAA(true):
+	case I3C_CCC_RSTDAA(false):
+	case I3C_CCC_ENTDAA:
+	case I3C_CCC_SETMWL(true):
+	case I3C_CCC_SETMWL(false):
+	case I3C_CCC_SETMRL(true):
+	case I3C_CCC_SETMRL(false):
+	case I3C_CCC_SETDASA:
+	case I3C_CCC_SETNEWDA:
+	case I3C_CCC_GETMWL:
+	case I3C_CCC_GETMRL:
+	case I3C_CCC_GETPID:
+	case I3C_CCC_GETBCR:
+	case I3C_CCC_GETDCR:
+	case I3C_CCC_GETSTATUS:
+	case I3C_CCC_GETMXDS:
+		return true;
+	default:
+		return false;
+	}
+}
+
+static int xi3c_master_send_bdcast_ccc_cmd(struct xi3c_master *master,
+					   struct i3c_ccc_cmd *ccc)
+{
+	struct xi3c_xfer *xfer __free(kfree) = NULL;
+	u8 *buf __free(kfree) = NULL;
+	struct xi3c_cmd *cmd;
+	u16 xfer_len;
+	int ret;
+
+	if (ccc->dests[0].payload.len >= XI3C_MAXDATA_LENGTH)
+		return -EINVAL;
+
+	xfer_len = ccc->dests[0].payload.len + 1;
+
+	xfer = xi3c_master_alloc_xfer(1);
+	if (!xfer)
+		return -ENOMEM;
+
+	buf = kmalloc(xfer_len, GFP_KERNEL);
+	if (!buf)
+		return -ENOMEM;
+
+	buf[0] = ccc->id;
+	memcpy(&buf[1], ccc->dests[0].payload.data, ccc->dests[0].payload.len);
+
+	cmd = &xfer->cmds[0];
+	cmd->addr = ccc->dests[0].addr;
+	cmd->rnw = ccc->rnw;
+	cmd->tx_buf = buf;
+	cmd->tx_len = xfer_len;
+	cmd->type = XI3C_SDR_MODE;
+	cmd->tid = XI3C_SDR_TID;
+	cmd->continued = false;
+
+	ret = xi3c_master_common_xfer(master, xfer);
+	ccc->err = cmd->err;
+
+	return ret;
+}
+
+static int xi3c_master_send_direct_ccc_cmd(struct xi3c_master *master,
+					   struct i3c_ccc_cmd *ccc)
+{
+	struct xi3c_xfer *xfer __free(kfree) = NULL;
+	struct xi3c_cmd *cmd;
+	int ret;
+
+	if (ccc->dests[0].payload.len > XI3C_MAXDATA_LENGTH)
+		return -EINVAL;
+
+	xfer = xi3c_master_alloc_xfer(2);
+	if (!xfer)
+		return -ENOMEM;
+
+	/* Broadcasted message */
+	cmd = &xfer->cmds[0];
+	cmd->addr = I3C_BROADCAST_ADDR;
+	cmd->rnw = false;
+	cmd->tx_buf = &ccc->id;
+	cmd->tx_len = 1;
+	cmd->type = XI3C_SDR_MODE;
+	cmd->tid = XI3C_SDR_TID;
+	cmd->continued = true;
+
+	/* Directed message */
+	cmd = &xfer->cmds[1];
+	cmd->addr = ccc->dests[0].addr;
+	cmd->rnw = ccc->rnw;
+	if (cmd->rnw) {
+		cmd->rx_buf = ccc->dests[0].payload.data;
+		cmd->rx_len = ccc->dests[0].payload.len;
+	} else {
+		cmd->tx_buf = ccc->dests[0].payload.data;
+		cmd->tx_len = ccc->dests[0].payload.len;
+	}
+	cmd->type = XI3C_SDR_MODE;
+	cmd->tid = XI3C_SDR_TID;
+	cmd->continued = false;
+
+	ret = xi3c_master_common_xfer(master, xfer);
+
+	/*
+	 * Report the broadcast command's error if it failed, otherwise the
+	 * directed command's, so a NACK on either phase reaches the caller.
+	 */
+	ccc->err = xfer->cmds[0].err ? xfer->cmds[0].err : xfer->cmds[1].err;
+
+	return ret;
+}
+
+static int xi3c_master_send_ccc_cmd(struct i3c_master_controller *m,
+				    struct i3c_ccc_cmd *cmd)
+{
+	struct xi3c_master *master = to_xi3c_master(m);
+
+	if (cmd->id & I3C_CCC_DIRECT)
+		return xi3c_master_send_direct_ccc_cmd(master, cmd);
+
+	return xi3c_master_send_bdcast_ccc_cmd(master, cmd);
+}
+
+static int xi3c_master_i3c_xfers(struct i3c_dev_desc *dev,
+				 struct i3c_xfer *xfers,
+				 int nxfers, enum i3c_xfer_mode mode)
+{
+	struct i3c_master_controller *m = i3c_dev_get_master(dev);
+	struct xi3c_master *master = to_xi3c_master(m);
+	struct xi3c_xfer *xfer __free(kfree) = NULL;
+	int i, ret;
+
+	if (!nxfers)
+		return 0;
+
+	if (mode != I3C_SDR)
+		return -EOPNOTSUPP;
+
+	for (i = 0; i < nxfers; i++)
+		if (xfers[i].len > XI3C_MAXDATA_LENGTH)
+			return -EINVAL;
+
+	xfer = xi3c_master_alloc_xfer(nxfers);
+	if (!xfer)
+		return -ENOMEM;
+
+	for (i = 0; i < nxfers; i++) {
+		struct xi3c_cmd *cmd = &xfer->cmds[i];
+
+		cmd->addr = dev->info.dyn_addr;
+		cmd->rnw = xfers[i].rnw;
+
+		if (cmd->rnw) {
+			cmd->rx_buf = xfers[i].data.in;
+			cmd->rx_len = xfers[i].len;
+		} else {
+			cmd->tx_buf = xfers[i].data.out;
+			cmd->tx_len = xfers[i].len;
+		}
+
+		cmd->type = XI3C_SDR_MODE;
+		cmd->tid = XI3C_SDR_TID;
+		cmd->continued = (i + 1) < nxfers;
+	}
+
+	ret = xi3c_master_common_xfer(master, xfer);
+
+	for (i = 0; i < nxfers; i++) {
+		xfers[i].err = xfer->cmds[i].err;
+		if (xfers[i].rnw)
+			xfers[i].actual_len = xfers[i].len - xfer->cmds[i].rx_len;
+	}
+
+	return ret;
+}
+
+static int xi3c_master_i2c_xfers(struct i2c_dev_desc *dev,
+				 struct i2c_msg *xfers,
+				 int nxfers)
+{
+	struct i3c_master_controller *m = i2c_dev_get_master(dev);
+	struct xi3c_master *master = to_xi3c_master(m);
+	struct xi3c_xfer *xfer __free(kfree) = NULL;
+	int i;
+
+	if (!nxfers)
+		return 0;
+
+	for (i = 0; i < nxfers; i++)
+		if (xfers[i].len > XI3C_MAXDATA_LENGTH)
+			return -EINVAL;
+
+	xfer = xi3c_master_alloc_xfer(nxfers);
+	if (!xfer)
+		return -ENOMEM;
+
+	for (i = 0; i < nxfers; i++) {
+		struct xi3c_cmd *cmd = &xfer->cmds[i];
+
+		cmd->addr = xfers[i].addr & XI3C_ADDR_MASK;
+		cmd->rnw = !!(xfers[i].flags & I2C_M_RD);
+
+		if (cmd->rnw) {
+			cmd->rx_buf = xfers[i].buf;
+			cmd->rx_len = xfers[i].len;
+		} else {
+			cmd->tx_buf = xfers[i].buf;
+			cmd->tx_len = xfers[i].len;
+		}
+
+		cmd->type = XI3C_I2C_MODE;
+		cmd->tid = XI3C_I2C_TID;
+		cmd->continued = (i + 1) < nxfers;
+	}
+
+	return xi3c_master_common_xfer(master, xfer);
+}
+
+static int xi3c_clk_cfg(struct xi3c_master *master, unsigned long sclhz, u8 mode)
+{
+	unsigned long core_rate, core_periodns;
+	u32 tcasmin, tsustart, tsustop, thdstart;
+	u32 thigh, tlow, thold;
+	u32 odthigh, odtlow;
+
+	core_rate = clk_get_rate(master->pclk);
+	if (!core_rate)
+		return -EINVAL;
+
+	if (!sclhz)
+		return -EINVAL;
+
+	core_periodns = DIV_ROUND_UP(NSEC_PER_SEC, core_rate);
+
+	thigh = DIV_ROUND_UP(core_rate, sclhz) >> 1;
+	tlow = thigh;
+
+	if (thigh <= XI3C_CYCLE_ADJUST)
+		return -EINVAL;
+
+	/* Hold time : 40% of tlow time */
+	thold = (tlow * 4) / 10;
+
+	if (xi3c_get_revision_number(master) == 0)
+		thold = max_t(u32, thold, XI3C_THOLD_MIN_REV0);
+	else
+		thold = max_t(u32, thold, XI3C_THOLD_MIN_REV1);
+
+	iowrite32((thigh - XI3C_CYCLE_ADJUST) & XI3C_TIMING_MASK,
+		  master->membase + XI3C_SCL_HIGH_TIME_OFFSET);
+	iowrite32((tlow - XI3C_CYCLE_ADJUST) & XI3C_TIMING_MASK,
+		  master->membase + XI3C_SCL_LOW_TIME_OFFSET);
+	iowrite32((thold - XI3C_CYCLE_ADJUST) & XI3C_TIMING_MASK,
+		  master->membase + XI3C_SDA_HOLD_TIME_OFFSET);
+
+	if (mode == XI3C_I2C_MODE) {
+		iowrite32((thigh - XI3C_CYCLE_ADJUST) & XI3C_TIMING_MASK,
+			  master->membase + XI3C_OD_SCL_HIGH_TIME_OFFSET);
+		iowrite32((tlow - XI3C_CYCLE_ADJUST) & XI3C_TIMING_MASK,
+			  master->membase + XI3C_OD_SCL_LOW_TIME_OFFSET);
+
+		tcasmin = DIV_ROUND_UP(XI3C_I2C_TCASMIN_NS, core_periodns);
+	} else {
+		odtlow = DIV_ROUND_UP(XI3C_OD_TLOW_NS, core_periodns);
+		odthigh = DIV_ROUND_UP(XI3C_OD_THIGH_NS, core_periodns);
+
+		odtlow = max(tlow, odtlow);
+		odthigh = min(thigh, odthigh);
+
+		if (odthigh <= XI3C_CYCLE_ADJUST)
+			return -EINVAL;
+
+		iowrite32((odthigh - XI3C_CYCLE_ADJUST) & XI3C_TIMING_MASK,
+			  master->membase + XI3C_OD_SCL_HIGH_TIME_OFFSET);
+		iowrite32((odtlow - XI3C_CYCLE_ADJUST) & XI3C_TIMING_MASK,
+			  master->membase + XI3C_OD_SCL_LOW_TIME_OFFSET);
+
+		tcasmin = DIV_ROUND_UP(XI3C_TCASMIN_NS, core_periodns);
+	}
+
+	thdstart = max(thigh, tcasmin);
+	tsustart = max(tlow, tcasmin);
+	tsustop = max(tlow, tcasmin);
+
+	iowrite32((tsustart - XI3C_CYCLE_ADJUST) & XI3C_TIMING_MASK,
+		  master->membase + XI3C_TSU_START_OFFSET);
+	iowrite32((thdstart - XI3C_CYCLE_ADJUST) & XI3C_TIMING_MASK,
+		  master->membase + XI3C_THD_START_OFFSET);
+	iowrite32((tsustop - XI3C_CYCLE_ADJUST) & XI3C_TIMING_MASK,
+		  master->membase + XI3C_TSU_STOP_OFFSET);
+
+	return 0;
+}
+
+static int xi3c_master_bus_init(struct i3c_master_controller *m)
+{
+	struct xi3c_master *master = to_xi3c_master(m);
+	struct i3c_bus *bus = i3c_master_get_bus(m);
+	struct i3c_device_info info = {};
+	unsigned long sclhz;
+	u32 pid1_bcr_dcr;
+	u8 mode;
+	int ret;
+
+	switch (bus->mode) {
+	case I3C_BUS_MODE_MIXED_FAST:
+	case I3C_BUS_MODE_MIXED_LIMITED:
+	case I3C_BUS_MODE_MIXED_SLOW:
+		mode = XI3C_I2C_MODE;
+		sclhz = bus->scl_rate.i2c;
+		break;
+	case I3C_BUS_MODE_PURE:
+		mode = XI3C_SDR_MODE;
+		sclhz = bus->scl_rate.i3c;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	ret = xi3c_clk_cfg(master, sclhz, mode);
+	if (ret)
+		return ret;
+
+	xi3c_master_init(master);
+
+	/* Get an address for the master. */
+	ret = i3c_master_get_free_addr(m, 0);
+	if (ret < 0)
+		return ret;
+
+	info.dyn_addr = ret;
+
+	/* Write the dynamic address value to the address register. */
+	iowrite32(info.dyn_addr, master->membase + XI3C_ADDRESS_OFFSET);
+
+	/* Read PID, BCR and DCR values, and assign to i3c device info. */
+	pid1_bcr_dcr = ioread32(master->membase + XI3C_PID1_BCR_DCR);
+	info.pid = ((u64)FIELD_GET(XI3C_PID1_MASK, pid1_bcr_dcr) << 32) |
+		   ioread32(master->membase + XI3C_PID0_OFFSET);
+	info.bcr = FIELD_GET(XI3C_BCR_MASK, pid1_bcr_dcr);
+	info.dcr = FIELD_GET(XI3C_DCR_MASK, pid1_bcr_dcr);
+
+	return i3c_master_set_info(&master->base, &info);
+}
+
+static void xi3c_master_bus_cleanup(struct i3c_master_controller *m)
+{
+	struct xi3c_master *master = to_xi3c_master(m);
+
+	xi3c_master_disable(master);
+}
+
+static const struct i3c_master_controller_ops xi3c_master_ops = {
+	.bus_init = xi3c_master_bus_init,
+	.bus_cleanup = xi3c_master_bus_cleanup,
+	.do_daa = xi3c_master_do_daa,
+	.supports_ccc_cmd = xi3c_master_supports_ccc_cmd,
+	.send_ccc_cmd = xi3c_master_send_ccc_cmd,
+	.i3c_xfers = xi3c_master_i3c_xfers,
+	.i2c_xfers = xi3c_master_i2c_xfers,
+};
+
+static int xi3c_master_probe(struct platform_device *pdev)
+{
+	struct xi3c_master *master;
+	int ret;
+
+	master = devm_kzalloc(&pdev->dev, sizeof(*master), GFP_KERNEL);
+	if (!master)
+		return -ENOMEM;
+
+	master->dev = &pdev->dev;
+
+	master->membase = devm_platform_ioremap_resource(pdev, 0);
+	if (IS_ERR(master->membase))
+		return dev_err_probe(master->dev, PTR_ERR(master->membase),
+				     "Failed to map registers\n");
+
+	master->pclk = devm_clk_get_enabled(master->dev, NULL);
+	if (IS_ERR(master->pclk))
+		return dev_err_probe(master->dev, PTR_ERR(master->pclk),
+				     "Failed to get and enable clock\n");
+
+	ret = devm_mutex_init(master->dev, &master->lock);
+	if (ret)
+		return ret;
+
+	platform_set_drvdata(pdev, master);
+
+	return i3c_master_register(&master->base, master->dev,
+				   &xi3c_master_ops, false);
+}
+
+static void xi3c_master_remove(struct platform_device *pdev)
+{
+	struct xi3c_master *master = platform_get_drvdata(pdev);
+
+	i3c_master_unregister(&master->base);
+}
+
+static const struct of_device_id xi3c_master_of_ids[] = {
+	{ .compatible = "xlnx,axi-i3c-1.0" },
+	{ },
+};
+MODULE_DEVICE_TABLE(of, xi3c_master_of_ids);
+
+static struct platform_driver xi3c_master_driver = {
+	.probe = xi3c_master_probe,
+	.remove = xi3c_master_remove,
+	.driver = {
+		.name = "axi-i3c-master",
+		.of_match_table = xi3c_master_of_ids,
+	},
+};
+module_platform_driver(xi3c_master_driver);
+
+MODULE_AUTHOR("Manikanta Guntupalli <manikanta.guntupalli@amd.com>");
+MODULE_AUTHOR("Shubhrajyoti Datta <shubhrajyoti.datta@amd.com>");
+MODULE_AUTHOR("Shubham Patil <shubhamsanjay.patil@amd.com>");
+MODULE_DESCRIPTION("AMD AXI I3C master driver");
+MODULE_LICENSE("GPL");
-- 
2.34.1

Re: [PATCH v9 1/2] dt-bindings: i3c: Add AMD I3C master controller support

[Pandey, Radhey Shyam]

> From: Manikanta Guntupalli <manikanta.guntupalli@amd.com>
> 
> Add device tree binding documentation for the AMD I3C master controller
> version 1.0.
> 
> Signed-off-by: Manikanta Guntupalli <manikanta.guntupalli@amd.com>
> Reviewed-by: Rob Herring (Arm) <robh@kernel.org>

It's missing your SOB.

Any further SoBs (Signed-off-by:s) following the author SoB are
from people handling and transporting the patch, but were not
involved in its development.


> ---
> Changes for V9:
> None.
It's not correct - you updated maintainer section in yaml?

> 
> Changes for V8:
> None.
> 
> Changes for V7:
> Added i3c controller version details to commit description.
> 
> Changes for V6:
> Corrected the file name for $id in yaml to fix the dtschema warning.
> 
> Changes for V5:
> Renamed the xlnx,axi-i3c.yaml file into xlnx,axi-i3c-1.0.yaml.
> 
> Changes for V4:
> Added h/w documentation details.
> 
> Changes for V3:
> Updated commit description.
> Corrected the order of properties and removed resets property.
> Added compatible to required list.
> Added interrupts to example.
> 
> Changes for V2:
> Updated commit subject and description.
> Moved allOf to after required.
> Removed xlnx,num-targets property.
> ---
>   .../bindings/i3c/xlnx,axi-i3c-1.0.yaml        | 56 +++++++++++++++++++
>   1 file changed, 56 insertions(+)
>   create mode 100644 Documentation/devicetree/bindings/i3c/xlnx,axi-i3c-1.0.yaml
> 
> diff --git a/Documentation/devicetree/bindings/i3c/xlnx,axi-i3c-1.0.yaml b/Documentation/devicetree/bindings/i3c/xlnx,axi-i3c-1.0.yaml
> new file mode 100644
> index 000000000000..75f677696f02
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/i3c/xlnx,axi-i3c-1.0.yaml
> @@ -0,0 +1,56 @@
> +# SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/i3c/xlnx,axi-i3c-1.0.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: AMD I3C master
> +
> +maintainers:
> +  - Shubhrajyoti Datta <shubhrajyoti.datta@amd.com>
> +  - Shubham Patil <shubhamsanjay.patil@amd.com>
> +
> +description:
> +  The AXI-I3C IP is an I3C Controller with an AXI4-Lite interface, compatible
> +  with the MIPI I3C Specification v1.1.1. The design includes bidirectional I/O
> +  buffers that implement open collector drivers for the SDA and SCL signals.
> +  External pull-up resistors are required to properly hold the bus at a Logic-1
> +  level when the drivers are released.
> +
> +  For more details, please see https://docs.amd.com/r/en-US/pg439-axi-i3c
> +
> +properties:
> +  compatible:
> +    const: xlnx,axi-i3c-1.0
> +
> +  reg:
> +    maxItems: 1
> +
> +  clocks:
> +    maxItems: 1
> +
> +  interrupts:
> +    maxItems: 1
> +
> +required:
> +  - compatible
> +  - reg
> +  - clocks
> +
> +allOf:
> +  - $ref: i3c.yaml#
> +
> +unevaluatedProperties: false
> +
> +examples:
> +  - |
> +    i3c@80000000 {
> +        compatible = "xlnx,axi-i3c-1.0";
> +        reg = <0x80000000 0x10000>;
> +        clocks = <&zynqmp_clk 71>;
> +        interrupt-parent = <&imux>;
> +        interrupts = <0 89 4>;

Nit - Don't use hard-coded numbers.
> +        #address-cells = <3>;
> +        #size-cells = <0>;
> +    };
> +...